This invention relates to deadbolts or locks for securing doors and the like, and will be disclosed in its adaptation to a multiplicity of automobile doors and subject to the operation of that type of vehicle. It is an object of this invention to provide security, and for example to prevent access or "breaking of the close" and alternately to permit access for ingress and egress. Heretofore, most locks have been key operated or combination operated, with mechanical limitations on key distinction and/or combination, and consequently subject to insercurity. That is, lock tumbler positioning can be determined by outsiders, or thieves and the like, and pass keys are available; all to the end that mechanical lock security is restricted and not entirely reliable. A state of the art locking device of the type under consideration utilizes electronics for the release of a deadbolt, as disclosed in U.S. Pat. No. 3,733,861 issued to Robert W. Lester May 22, 1973 and entitled ELECTRONIC RECOGNITION DOOR LOCK, wherein a transponder transmits a range of ultrasonic signals of varying frequency, which equal a code sequentially both in time, length and frequency. The three sequential timed signals are received by transducers and transmitted to a shift register that activates a bolt releasing solenoid, only after signals are received in the proper sequence. The Lester system is feasible but is unnecessarily complicated and restrictive through its indirect mode of operation, and therefore not entirely practical. Accordingly, it is an object of this invention to provide an improved electronic security system having a direct mode of operation over locked devices and closures, whereby the lock closing and opening codes are not only unpredictable but are substantially increased in number of the combinations available for greater security; the digital signals used herein being distinct "passive codes".